CVE-2025-15533 identifies a heap-based buffer overflow vulnerability in the raysan5 raylib open-source graphics library, specifically in the GenImageFontAtlas function located in src/rtext.c. This function is responsible for generating font atlases used in rendering text images. The vulnerability arises from improper handling of input data sizes, leading to a buffer overflow on the heap when manipulated inputs exceed expected bounds. The overflow can corrupt adjacent memory, potentially allowing an attacker to alter program behavior, cause crashes, or execute arbitrary code. Exploitation requires local access with limited privileges, no user interaction, and no authentication bypass, limiting the attack vector to local users or processes. The CVSS 4.0 base score of 4.8 reflects medium severity, considering the local attack vector and limited impact on confidentiality, integrity, and availability. The vulnerability has been publicly disclosed, increasing the risk of exploitation, although no active exploits have been reported. A patch identified by commit 5a3391fdce046bc5473e52afbd835dd2dc127146 has been released to fix the issue by correcting input validation and buffer management in the affected function. Organizations using raylib, especially in development or local runtime environments, should apply this patch to prevent potential exploitation.

For European organizations, the primary impact of CVE-2025-15533 lies in the potential for local privilege escalation or denial of service in applications using raylib for graphics rendering or game development. While the vulnerability requires local access, it could be leveraged by malicious insiders or through compromised local accounts to disrupt services or gain unauthorized code execution capabilities. This may affect software development firms, multimedia companies, and educational institutions using raylib in their workflows. The impact on confidentiality, integrity, and availability is limited but non-negligible, as heap corruption can lead to application crashes or data manipulation. Given the medium severity and local attack vector, the threat is less critical for large-scale remote attacks but remains relevant for organizations with shared workstations or multi-user environments. Failure to patch could lead to increased risk of exploitation as public disclosure raises attacker awareness.

To mitigate CVE-2025-15533, European organizations should immediately apply the official patch (commit 5a3391fdce046bc5473e52afbd835dd2dc127146) to all affected raylib versions, specifically those up to 909f040. Additionally, organizations should audit and restrict local user permissions to minimize the number of users who can execute or manipulate applications using raylib. Implementing strict access controls and monitoring local system activity can help detect and prevent exploitation attempts. Developers should review their use of the GenImageFontAtlas function to ensure inputs are properly sanitized and consider employing additional runtime protections such as heap integrity checks or memory-safe coding practices. Regularly updating dependencies and integrating vulnerability scanning into the software development lifecycle will reduce exposure to similar issues. Finally, educating local users about the risks of executing untrusted code can further reduce attack surface.